At the present time in digital radios, a multiplicity of formats for broadcast band transmission is in use. The common factor is the inclusion, in a transmitted signal of at least one digitally modulated channel in the transmitted channel. Referring to FIG. 1, a block diagram of a digital radio 10, according to the prior art, is shown. The digital radio 10 includes an antenna unit 5. The antenna unit can be a part of the digital radio 10 or can be coupled to the digital radio by a conducting element. The signals picked up by the antenna 5 are applied to the receiver unit/down-converter unit 101. The output signals of the receiver unit/down-converter unit 101 are modulated signals having an intermediate frequency. The receiver unit/down-converter unit 101 applies the intermediate frequency signals to analog-to-digital converter unit 102. The analog-to-digital converter 102 converts the digitally-encoded signal carriers and the analog-encoded signal carriers to digital serial data. The output signals from the analog-to-digital converter are applied to the demodulator unit/processor unit 103. The demodulator unit/processor unit 103 demodulates and decodes both the analog and digital transmitted signal content. The analog and digital signal channel signals are applied to the demodulator unit/processing unit 103 together, but are demodulated and processed separately in the unit 103. The demodulator unit/processing unit 103 exchanges program and data signals with the memory unit 104. The processing unit 103, in response to a user input and the program stored in memory unit 104, processes the signals received from the analog-to-digital converter unit 102. For example, a decompression algorithm can be applied to the received signals. The processed signals from the demodulator unit/processing unit 103 are applied to digital to analog converter unit 105. The output signals from the digital to analog converter are applied through amplifying units 109 through 110 to speaker unit 107 through 108, respectively.
As will be clear to those skilled in the art, the foregoing description is meant to be illustrative rather than comprehensive. Part of the problem resides in the fact that at the present time, the format of the digital radio broadcast band has not been standardized. As indicated above, the definition of a digital radio broadcast band includes the requirement that at least one of the channels within the broadcast band is encoded digitally. The remaining channels can be encoded with analog and/or digital encoding. Typically, the broadcast band includes a performance channel, the contents of which are applied to the digital radio's speakers for the user. In addition, generally, at least one digital channel, referred hereinafter as the information channel, includes the identification of the properties of an associated performance band or performance bands. The properties can include an identification of the performance piece, the principal artists, the category or categories best identifying the piece, the type of performance pieces broadcast in the transmission band, etc. In some implementations, the performance channel(s) is (are) combined with the information channel(s). The properties of the associated performance channel(s) can be presented to the user as audio or visual information permitting the user to make a choice that can be entered manually in the digital radio.
The entry of the user input alters the configuration of the digital radio. When the information channel identifies a category of material broadcast over this band or the category of an associated performance piece, the user can use a technique generally referred to as equalization to enhance the performance. In equalization, the frequency spectrum of the demodulated and decoded performance piece is divided into a plurality of frequency bands. The amplification of the frequency bands is selected for each frequency region to enhance the performance, for the user, for that particular category of performance piece. The user can be provided with controls so the equalization can be performed for each performance piece or for a plurality of similar performance pieces.
A need has therefore been felt for apparatus and an associated method having the feature that the information band of a digital radio broadcast band can used to control automatically the reproduction of the performance channel. It would be a further feature of the present invention to provide for apparatus monitoring the information channel of a digital radio broadcast band. It would be a still further feature of the apparatus and associated method to provide a digital radio that is automatically reconfigured in response to a selected signal group in the information channel of a digital signal broadcast band. It would be still further feature of the apparatus and associated method to control automatically and selectively the relative amplitudes of predetermined frequency ranges of demodulated, decoded performance channels.